Background:: The neutrophil lymphocyte ratio (NLR) has prognostic value in patients with a variety of cancers. Many chemotherapeutic trial databases hold information on white cell and neutrophil counts only. The aim of the present study was to compare the prognostic value of the NLR with a derived score (dNLR), composed of white cell and neutrophil counts. Methods:: Patients (n=27 031) who were sampled incidentally between 2000 and 2007 for neutrophil, lymphocyte and white cell counts, and also had a diagnosis of cancer (Scottish Cancer Registry), were identified. Of this group, 12 118 patients who had been sampled within 2 years of their cancer diagnosis were studied. Results:: On follow-up, there were 7366 deaths, of which 6198 (84%) were cancer deaths. The median time from blood sampling to diagnosis was 2.1 months. The area under the receiver-operating characteristic (ROC) curve for cancer-specific survival was 0.650 for the NLR and 0.640 for the dNLR. The NLR and dNLR were independently associated with survival in all cancers studied (all P<0.001). The optimal thresholds, on the basis of hazard ratios and area under the curve, were 4 : 1 for the NLR and 2 : 1 for the dNLR. Conclusion:: The results of the present study show that the dNLR has similar prognostic value to the NLR. Therefore, the universally available dNLR is to be commended for use in the risk stratification of patients undergoing chemotherapy.